On Tue, Oct 29, 2019 at 05:38:02PM -0400, Raphael Norwitz wrote:
> Add a VHOST_USER_RESET_DEVICE message which will reset the vhost user
> backend. Disabling all rings, and resetting all internal state, ready
> for the backend to be reinitialized.
>
> A backend has to report it supports this features with the
> VHOST_USER_PROTOCOL_F_RESET_DEVICE protocol feature bit. If it does
> so, the new message is used instead of sending a RESET_OWNER which has
> had inconsistent implementations.
>
> Signed-off-by: David Vrabel <david.vra...@nutanix.com>
> Signed-off-by: Raphael Norwitz <raphael.norw...@nutanix.com>
Looks ok, pls ping me after the release to apply this.
> ---
> docs/interop/vhost-user.rst | 15 +++++++++++++++
> hw/virtio/vhost-user.c | 8 +++++++-
> 2 files changed, 22 insertions(+), 1 deletion(-)
>
> diff --git a/docs/interop/vhost-user.rst b/docs/interop/vhost-user.rst
> index 7827b71..d213d4a 100644
> --- a/docs/interop/vhost-user.rst
> +++ b/docs/interop/vhost-user.rst
> @@ -785,6 +785,7 @@ Protocol features
> #define VHOST_USER_PROTOCOL_F_SLAVE_SEND_FD 10
> #define VHOST_USER_PROTOCOL_F_HOST_NOTIFIER 11
> #define VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD 12
> + #define VHOST_USER_PROTOCOL_F_RESET_DEVICE 13
>
> Master message types
> --------------------
> @@ -1190,6 +1191,20 @@ Master message types
> ancillary data. The GPU protocol is used to inform the master of
> rendering state and updates. See vhost-user-gpu.rst for details.
>
> +``VHOST_USER_RESET_DEVICE``
> + :id: 34
> + :equivalent ioctl: N/A
> + :master payload: N/A
> + :slave payload: N/A
> +
> + Ask the vhost user backend to disable all rings and reset all
> + internal device state to the initial state, ready to be
> + reinitialized. The backend retains ownership of the device
> + throughout the reset operation.
> +
> + Only valid if the ``VHOST_USER_PROTOCOL_F_RESET_DEVICE`` protocol
> + feature is set by the backend.
> +
> Slave message types
> -------------------
>
> diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c
> index 02a9b25..d27a10f 100644
> --- a/hw/virtio/vhost-user.c
> +++ b/hw/virtio/vhost-user.c
> @@ -58,6 +58,7 @@ enum VhostUserProtocolFeature {
> VHOST_USER_PROTOCOL_F_SLAVE_SEND_FD = 10,
> VHOST_USER_PROTOCOL_F_HOST_NOTIFIER = 11,
> VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD = 12,
> + VHOST_USER_PROTOCOL_F_RESET_DEVICE = 13,
> VHOST_USER_PROTOCOL_F_MAX
> };
>
> @@ -98,6 +99,7 @@ typedef enum VhostUserRequest {
> VHOST_USER_GET_INFLIGHT_FD = 31,
> VHOST_USER_SET_INFLIGHT_FD = 32,
> VHOST_USER_GPU_SET_SOCKET = 33,
> + VHOST_USER_RESET_DEVICE = 34,
> VHOST_USER_MAX
> } VhostUserRequest;
>
> @@ -890,10 +892,14 @@ static int vhost_user_set_owner(struct vhost_dev *dev)
> static int vhost_user_reset_device(struct vhost_dev *dev)
> {
> VhostUserMsg msg = {
> - .hdr.request = VHOST_USER_RESET_OWNER,
> .hdr.flags = VHOST_USER_VERSION,
> };
>
> + msg.hdr.request = virtio_has_feature(dev->protocol_features,
> + VHOST_USER_PROTOCOL_F_RESET_DEVICE)
> + ? VHOST_USER_RESET_DEVICE
> + : VHOST_USER_RESET_OWNER;
> +
> if (vhost_user_write(dev, &msg, NULL, 0) < 0) {
> return -1;
> }
> --
> 1.8.3.1
